I have a Seagate 1.4TB external drive with a dedicated power cord; and mine also isn't being detected. Tried it unsuccessfully on 4 machines: Windows XP, Linux Ubuntu, an Apple Mac and a Toshiba Android tablet. No go. It makes whirring sounds for a few seconds then quits.

2 Answers

Assuming the drive is ok (have you tested it on another computer) it might be, that it demands too much current from the USB port - had this with an older FSC drive (I think with a Seagate or WD drive builtin).

External HD is composed by two parts: a controller and a classic HD. I would try to open it and conect the HD directly to the mainboard with the right interface (sata or parallel) ... if it works by anothe case/controller (very cheap) if it's not recognised ... it's above my knowledge ....